Codes P1165 and P1145, Rough Idle but no CEL

[nguye569]

I had some weird symptoms coming up with my car with no CEL lights (see below), took it in and the codes P1165 and P1145 showed up when they ran diagnostics. P1145 should be easily fixed by me replacing the sensor. I'm having a little trouble finding any more information for P1165. Mechanic said I need to replace the Swirl control valve control vacuum check switch and showed me where it is. Anyone know what this thing does and if it'll fix my problem? See this link for image that I found someone else post, http://www.the510realm.com/viewtopic.php?f=2&t=10191.

Symptoms of car - rough idle and driving once car is warmed up. In low speeds rough idle and power seems a bit weak. At higher speeds, if accelarating, can defn feel it's week between 2000 and 2500 RPM and will even shake as if it's starving for air or gas. If I step on gas hard enough, I don't notice it.

[Buzzman]

What year and what model?

[nguye569]

What year and what model?

2001 Infiniti QX4 with 208k miles. Aside from the rough idle and drive, there arent any indications of something wrong with the car. I just fail to see how these two item are causing my problems.

[rgk]

The first step is to find out if the check switch hose is split or clogged. If the hose is ok, check to see if one of the prongs on the electrical connector has continuity with ground. You'll need an ohmmeter for this.

Additionally, I would check all of the hoses and solenoids under the hood for good measure.